Humeral Condylar Fissure

Humeral Condylar Fissure (HCF), Humeral Intra-Condylar Fissure (HIF) and Incomplete Ossification of the Humeral Condyle (IOHC) are different names for the same condition. This is a condition whereby a fissure develops between the two halves of the humeral condyle that forms the upper part of the elbow joint.

It can occur at any age but is typically seen in young to middle aged dogs, and typically affects Spaniel breeds although it can affect any breed. Nobody really knows why the fissure develops; it used to be thought to be a developmental problem occurring in the growing puppy, but we know it can also develop in adult dogs. Usually once present, the fissure is there for life and, despite treatment, the bone will not heal; in very rare cases the fissure has been documented to heal, but this is the exception.

Fissures are not all the same — they can be very small, incomplete, complete, or complete and very wide. There is no way of predicting fissure progression, including whether it will lead to bone fracture or not. X-rays are insensitive to HIF; the best way to diagnose it is with a CT scan.

HIF should be suspected in an adult dog with forelimb lameness when no other cause can be found, particularly in Spaniel breeds. Management options are:

• Surgery — the current best standard of care is to place a screw across the humeral condyle to stabilise the fissure. The intention of the screw is to stabilise the condyle, resolve lameness and prevent fracture.
• Conservative (non-surgical) management — if the fissure is diagnosed incidentally with no history of lameness, it is reasonable not to operate; however, the larger the fissure, the more carefully this decision has to be made. One approach is to monitor fissure stability vs. progression through repeated CT scans every 3–12 months.

In a dog that has had signs of lameness associated with a fissure, it is estimated that the chance of the fissure causing a problem on the other leg is about 20%. Fractures result from fissures that are undiagnosed or not treated, and can be a lateral, medial, or very nasty Y or T bicondylar elbow fracture; these are very difficult and expensive to repair.

In general, the goals of the screw — to stabilise the condyle, resolve lameness and prevent fracture — are successfully achieved.

The vast majority of dogs with transcondylar screw placement do extremely well with rapid, complete and permanent resolution of the lameness.

However, placement of the screw carries risks of infection, seroma formation over the screw, screw loosening and backing out, screw fracture, or inadvertent placement of the screw into the joint. The published complication rate of screw placement is up to 40%, but in our experience it is closer to 10%. A minority of dogs have problems; most can be resolved, but if problems happen they can be time-consuming, frustrating and expensive to manage successfully.